From e6d26b3c3214ac8d0bc712d15d132a69d7952fca Mon Sep 17 00:00:00 2001 From: Ricky Kendall Date: Mon, 21 Oct 1996 19:13:13 +0000 Subject: [PATCH] added continue directive information rak --- doc/user/mp2.tex | 30 ++++++++++++------------ doc/user/top-level.tex | 53 ++++++++++++++++++++++++++++++------------ 2 files changed, 53 insertions(+), 30 deletions(-) diff --git a/doc/user/mp2.tex b/doc/user/mp2.tex index 2a60454693..20b1bfbf8e 100644 --- a/doc/user/mp2.tex +++ b/doc/user/mp2.tex @@ -4,12 +4,12 @@ The RI-MP2 module can be invoked by specifying \begin{verbatim} TASK RI-MP2 \end{verbatim} -on a \verb+RESTART+ job -- the MO vectors and database from the SCF -calculation must be present. At present, the RI-MP2 does not have its -own input module, instead it can be controlled by \verb+SET+ing -entries in the database. Currently recognized entries are described -below. {\em The names of these entries in the database will change in -the very near future.} +on a \verb+RESTART+ or \verb+CONTINUE+ job -- the MO vectors and +database from the SCF calculation must be present. At present, the +RI-MP2 does not have its own input module, instead it can be +controlled by \verb+SET+ing entries in the database. Currently +recognized entries are described below. {\em The names of these + entries in the database will change in the very near future.} Alternatively, the fully-direct MP2 module using conventional four-index transformation (see also section \ref{sec:fourindex}) may be @@ -19,15 +19,15 @@ invoked by the input line \end{verbatim} In future releases, the two MP2 modules will be amalgamated into a single task where the choice of method will be an input parameter. In -cases where the MP2 is restarted using a \verb+RESTART+ directive -- -the MO vectors and database from the SCF calculation must be present. -Currently, there is no specific MP2 input module, instead the -behavior can be modified by using the \verb+SET+ command on the -database entries. Currently recognized entries are described below, -the first three entries apply to both the \verb+RI-MP2+ and -\verb+DIRECT_MP2+ tasks while the remainder are specific to -\verb+RI-MP2+. {\em The names of these entries in the database are -subject to change in the near future.} +cases where the MP2 is restarted using a \verb+RESTART+ or +\verb+CONTINUE+ directive -- the MO vectors and database from the SCF +calculation must be present. Currently, there is no specific MP2 +input module, instead the behavior can be modified by using the +\verb+SET+ command on the database entries. Currently recognized +entries are described below, the first three entries apply to both the +\verb+RI-MP2+ and \verb+DIRECT_MP2+ tasks while the remainder are +specific to \verb+RI-MP2+. {\em The names of these entries in the + database are subject to change in the near future.} \subsection{Frozen Orbitals} diff --git a/doc/user/top-level.tex b/doc/user/top-level.tex index 86ea4d647f..a9f32b2532 100644 --- a/doc/user/top-level.tex +++ b/doc/user/top-level.tex @@ -1,34 +1,57 @@ -\subsection{START and RESTART} +\subsection{START, CONTINUE and RESTART} \label{sec:start} This is a startup directive (section \ref{sec:inputstructure}). -A \verb+START+ or \verb+RESTART+ directive is optional but care must +A \verb+START+, \verb+CONTINUE+ or \verb+RESTART+ directive is optional but care must be taken if no directive is presented since the behaviour of the code will vary depending upon the existence of the database. \begin{verbatim} - (RESTART || START) [] [rtdb ] +(RESTART || CONTINUE || START) [] [rtdb ] \end{verbatim} \verb+START+ indicates a startup calculation in which the database is -created and any existing database is destroyed. \verb+RESTART+ -indicates that an existing database should be used and an error will -result if it does not exist. All files created by NWChem are by -default prefixed with the string specified on the directive, which -defaults to the basename of the input file (i.e., the input file name -with the directory and any trailing \verb+.*+ stripped off). Note -that if you change the file prefix in a restart job, NWChem will be -unable to locate most files automatically. The \verb+RTDB+ keyword -permits specification of the name of the database which otherwise -defaults to \verb+.db+ in the directory for permanent -files. +created and any existing database is destroyed. \verb+RESTART+ or +\verb+CONTINUE+ indicate that an existing database should be used and +an error will result if it does not exist. All files created by +NWChem are by default prefixed with the string specified on the +directive, which defaults to the basename of the input file (i.e., the +input file name with the directory and any trailing \verb+.*+ stripped +off). Note that if you change the file prefix in a restart job, +NWChem will be unable to locate most files automatically. The +\verb+RTDB+ keyword permits specification of the name of the database +which otherwise defaults to \verb+.db+ in the directory +for permanent files. -If no \verb+START+ or \verb+RESTART+ directive is presented then +The difference between \verb+CONTINUE+ and \verb+RESTART+ is subtle +but useful. \verb+CONTINUE+ will not parse any new input data before +it does the task stored in the database file. \verb+RESTART+ will +parse new input data and overwrite any existing data if appropriate. +\verb+CONTINUE+ should be viewed as {\it restart and finish} the +old task and also do any new tasks that are input. \verb+RESTART+ +should be viewed as restart with information available, new input is +also parsed, and do the tasks outlined in the input so the old task +may be discarded. \verb+CONTINUE+ implies restart the old task and +\verb+RESTART+ implies restart with possibly a new task. + +For example, in a SCF energy calculation where you underestimated the +time necessary and the job was killed by the scheduling software. You +could use either \verb+CONTINUE+ or \verb+RESTART+ directive with the +appropriate file prefix and database specifiction to complete the +task. On the other hand if you wanted to finish the task and do an +additional SCF energy computation with a new geometry you could use +\verb+CONTINUE+ directive, input the new geometry and use a single +task directive for the second energy point. Again, the difference is +subtle but useful. + +If no \verb+START+ \verb+CONTINUE+ or \verb+RESTART+ directive is +presented then \begin{itemize} \item the default file prefix is used, \item the default database name is used, \item if the default database exists, then the job is assumed to be a restart, otherwise it is assumed to be a startup. + \item continue is never assumed. \end{itemize} E.g., if running NWChem with the command \verb+nwchem water.nw+ and no